/*
* Copyright (C) 2013 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package android.util;
import static com.android.internal.util.Preconditions.checkNotNull;
/**
* Immutable class for describing width and height dimensions in pixels.
*/
public final class Size {
/**
* Create a new immutable Size instance.
*
* @param width The width of the size, in pixels
* @param height The height of the size, in pixels
*/
public Size(int width, int height) {
mWidth = width;
mHeight = height;
}
/**
* Get the width of the size (in pixels).
* @return width
*/
public int getWidth() {
return mWidth;
}
/**
* Get the height of the size (in pixels).
* @return height
*/
public int getHeight() {
return mHeight;
}
/**
* Check if this size is equal to another size.
* <p>
* Two sizes are equal if and only if both their widths and heights are
* equal.
* </p>
* <p>
* A size object is never equal to any other type of object.
* </p>
*
* @return {@code true} if the objects were equal, {@code false} otherwise
*/
@Override
public boolean equals(final Object obj) {
if (obj == null) {
return false;
}
if (this == obj) {
return true;
}
if (obj instanceof Size) {
Size other = (Size) obj;
return mWidth == other.mWidth && mHeight == other.mHeight;
}
return false;
}
/**
* Return the size represented as a string with the format {@code "WxH"}
*
* @return string representation of the size
*/
@Override
public String toString() {
return mWidth + "x" + mHeight;
}
private static NumberFormatException invalidSize(String s) {
throw new NumberFormatException("Invalid Size: \"" + s + "\"");
}
/**
* Parses the specified string as a size value.
* <p>
* The ASCII characters {@code \}{@code u002a} ('*') and
* {@code \}{@code u0078} ('x') are recognized as separators between
* the width and height.</p>
* <p>
* For any {@code Size s}: {@code Size.parseSize(s.toString()).equals(s)}.
* However, the method also handles sizes expressed in the
* following forms:</p>
* <p>
* "<i>width</i>{@code x}<i>height</i>" or
* "<i>width</i>{@code *}<i>height</i>" {@code => new Size(width, height)},
* where <i>width</i> and <i>height</i> are string integers potentially
* containing a sign, such as "-10", "+7" or "5".</p>
*
* <pre>{@code
* Size.parseSize("3*+6").equals(new Size(3, 6)) == true
* Size.parseSize("-3x-6").equals(new Size(-3, -6)) == true
* Size.parseSize("4 by 3") => throws NumberFormatException
* }</pre>
*
* @param string the string representation of a size value.
* @return the size value represented by {@code string}.
*
* @throws NumberFormatException if {@code string} cannot be parsed
* as a size value.
* @throws NullPointerException if {@code string} was {@code null}
*/
public static Size parseSize(String string)
throws NumberFormatException {
checkNotNull(string, "string must not be null");
int sep_ix = string.indexOf('*');
if (sep_ix < 0) {
sep_ix = string.indexOf('x');
}
if (sep_ix < 0) {
throw invalidSize(string);
}
try {
return new Size(Integer.parseInt(string.substring(0, sep_ix)),
Integer.parseInt(string.substring(sep_ix + 1)));
} catch (NumberFormatException e) {
throw invalidSize(string);
}
}
/**
* {@inheritDoc}
*/
@Override
public int hashCode() {
// assuming most sizes are <2^16, doing a rotate will give us perfect hashing
return mHeight ^ ((mWidth << (Integer.SIZE / 2)) | (mWidth >>> (Integer.SIZE / 2)));
}
private final int mWidth;
private final int mHeight;
}